1. Field of the Invention
The present invention generally relates to an optical imaging lens set and an electronic device which includes such optical imaging lens set. Specifically speaking, the present invention is directed to an optical imaging lens set of five lens elements and an electronic device which includes such optical imaging lens set of five lens elements.
2. Description of the Prior Art
In recent years, the popularity of mobile phones and digital cameras makes the photography modules of various portable electronic products, such as optical imaging lens elements or an image sensor . . . develop quickly, and the shrinkage of mobile phones and digital cameras also makes a greater and greater demand for the miniaturization of the photography module. The current trend of research is to develop an optical imaging lens set of a shorter length with uncompromised good quality.
With the development and shrinkage of a charge coupled device (CCD) or a complementary metal oxide semiconductor element (CMOS), the optical imaging lens set installed in the photography module shrinks to meet the demands as well. However, good and necessary optical properties, such as the system aberration improvement, as well as production cost and production feasibility should be taken into consideration, too.
For example, U.S. Pat. No. 8,289,628, U.S. Pat. No. 8,248,713 and US 2012/0194922 all disclose an optical imaging lens set made of five lens elements. In these structures, the image-side surface of the first lens element and the object-side surface of the second lens element are concave as a whole so that there is a fairly large gap between the two lens elements, and the total length of the optical imaging lens set is even up to 10 mm-18 mm. The imaging result is not ideal.
Further, U.S. Pat. No. 6,999,246, U.S. Pat. No. 7,903,349 and US 2010/0328730 all disclose another optical imaging lens set made of five lens elements. In these structures, the fifth lens element is convex as a whole so not both the total length and the imaging quality are always good enough.
These disclosed dimensions do not show good examples of the shrinkage of portable electronic products, such as mobile phones and digital cameras. It is still a problem, on one hand, to reduce the system length efficiently and, on the other hand, to maintain a sufficient optical performance in this field.